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I have never been one of those fearless descenders that flies down hills with reckless abandon, but I was no ninny, either. I loved speed and pushed my limits, but I never could let go completely, and always held back a little.

After I slid out and crashed while leaning into a tight turn at about 35 mph, I got a little gun shy and lost a little more of whatever edge I had, but I still had no problems going down hill fast and carving out turns. I was just a little slower.

Fast forward a few years. Now I ride a fraction of the miles I used to (for various reasons), and don't get up into the mountains very often. A few weeks ago, I descended a local climb that is normally a fun, fast and twisty descent. I started down and quickly realized that I had zero confidence in what I was doing. I was scared. I couldn't wait to get off the mountain, but it was a five mile descent, so it was going to take a while. I was very relieved when I hit the bottom.

Here's my question. I got a new bike a year or two ago, which fits me better than any bike I've ever owned. It has a 70mm stem, which is quite short. On the hoods, where I spend most of my time, the fit is perfect, but in the drops or on the tops it feels a little cramped. I'm sure this was part of why I lacked confidence on the bike (along with being rusty at descending). I know stem length affects steering speed, so is this true? Could the short stem have contributed to my lack of confidence? Would going to a longer stem help?
 

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Maybe, but I'd attribute it mostly to being out of the game, and perhaps to simply not being as familiar with this bike as others.

The net change in leverage is really rather small, so that's not a big deal. You may have changed your weight distribution (percentage of weight borne by front/rear wheels), and that could affect your confidence rather more.

IMO, the biggest single thing that changes handling feel in this context is the way weight is balanced between hands and saddle/pedals. More weight being borne by the hands results in a reduced sense of fine control, which depending on the other variables can be a good thing or bad.

A lot of folks advocate having weight relatively forward for descent, both in terms of weight distribution and body balance. Personally, I've always preferred rather aft weight, as it gives me a better sense of control (the handing gets stiff enough at speed, thank you very much) and increases my confidence in braking. I've never had much trouble 'steering' the bike due to front wheel steering washout, perhaps because I recognize handlebar movements as being for balance and leaning for steering. Not saying right or wrong, just that it's more a matter of personal preference and what you are accustomed to.
 

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thoughts...

A bike that requires a 70mm stem must not fit that great, unless it's just a case of preferring a cramped setup. My rule of thumb is to have enough stem length to avoid knee to arm interference when I'm pedaling with my upper back nearly horizontal and my hands are in the hooks, in reach of the brake levers.

A common problem with a stem that short would be knees hitting the bars when pedaling standing. If I were to drop down from a 110mm stem to a 100, I'd occasionally graze the bars.

I wouldn't expect a lot of descending confidence if you don't do it often. I do a 10 mile mountain descent, three times a week (in season). It always takes a few trips down to regain full confidence. In the early season, there is always sand on the road and it's easy to get over confident. After several hundred successful descents, I went down twice in one year. Once in the spring, on the only corner that was still wet and sandy, I was forced out of the clean strip by an oncoming truck and went down hard, but in hindsight, I was also going too fast. In the fall of that year I went down very unexpectedly, just due to the lack of traction from an early sanding of the road. I'm much more cautious now, until the roads get cleaned.
 

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a lot could also have to do with the bike geometry. if your angles are steeper on the new bike (especially the head tube) the bike will feel twitchier. i just got a newer, racier, lighter bike and i'm having the same issue. maybe not to the same extent, but it is nerve racking.

like you, i also switched to a shorter stem (90mm) along with a zero offset seatpost for a much shorter cockpit. it feels a little cramped on the fast descents, but overall i'm much more comfotrable everywhere else. i think it is a fair trade.

one other thing that i have changed is that i now have bladed spokes. i rode in a heavy crosswind and WOW! it was scary. i was getting blown all over the place. it was my first ride on the new bike and i was convinced that the bike was the twitchiest, raciest bike in the world. it took a few minutes to realize that it was the big fat spokes in the wind.
 

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C-40 said:
A bike that requires a 70mm stem must not fit that great, unless it's just a case of preferring a cramped setup.
How can you make that assumption without knowing the relative TT length and ST angles, one bike against another? As comparison, my wife's bike took a 70mm avoid being way too stretched out. Interference when climbing is absolutely not a problem. Meanwhile, a bike with a much longer stem would be close to unrideable in the toe-overlap arena for her - it's only an annoyance right now.

I'd be interested to know how Mohair finds his descending uncomfortable. My suspicion is that his new fit has lengthend his wheelbase and raised his head tube, effectively moving his weight distribution back. All together, this would make a bike that felt relatively 'light but slow' in the steering. A longer stem would do relatively little (absent other adjustments) to firm up the steering, but would make it slower stilll from the increased moment arm, as well as requiring marginally less effort.

If instead he's finding it heavy in action but quick in response, a longer stem may be useful. But I'd hesitate to recommend this adjustment out of hand, given that he seems to be otherwise happy with the fit and is apparently not in descending mode all that much. Fit is all about compromise, and perhaps becoming accustomed to the 'new' handling is all that's really required.
 

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Discussion Starter · #6 ·
The bike is a 50cm Trek Madone. My "previous" bike is a 51cm Litespeed Classic. I put tens of thousands of miles on the Litespeed before I finally gave in to the fact that it was too big.

I don't recall exactly what made me uncomfortable. While I have done this descent countless times in the past on the Litespeed, I had never done it on the Trek. The descent is rather sharp and twisty, which is why I suspect the steering and/or cramped cockpit while in the drops. I have done shorter high speed descents on the Trek that had wide, sweeping turns, with minimal braking, and I didn't feel uncomfortable at all. I guess it's not the speed, but the turning that is freaking me out.

I have not noticed any toe overlap issues, so that is not a factor.
 

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well...

To each his own, but I've got a really short torso and I'd never go under a 100mm stem.

I realize that most riders use standard reach bars and shimano brake/shift levers that have about 15mm more reach than my Campy lever and short reach bars, but that's exactly why I use them - to avoid the overly stubby stem and knee interference. I'd be hitting the bars with my knees, when standing if I had a 90mm stem. Most of the bests stem are not even made in a 70mm.
 

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Is there much of a difference in top tube lenght and seat tube angle between a 50 Trek madone and the too large Litespeed? Suspect they're close in angle and dimension. Most bikes have at least a 9/10cm stem. places the rider in better balance. a 70 means you might be too far forward. But most small frames 48-50 have nothing shorter than a 52.5cm top tube, which may still be too long.
 

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Maybe try a longer stem with some compact drop bars. You need to have enough stem to put weight over the front axle or else the gyroscopic force of the wheel is not as great and oops...there went your front wheel in a turn....

I ride a 90cm stem but would never race a crit with it because it doesnt give me enough weight over the axle for turns where i have no room to adjust.
 

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You're Not the Boss of Me
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Not necessarily... depends on the fork rake too. But as a practical matter, I think it is just going to be a matter of dusting off the descending skills.

The tiny bit of difference in stem length is easily addressed by sliding a little back on the saddle while descending, too.
 

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n00bsauce
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There's almost no difference in steering speed between stem lengths, even substantial stem length differences (say your 70mm and 150mm). Now, handlebar width can have a substantial affect. Did your handlebar width change?

Steering at speed is almost all body lean and very little actual steering input. Weight distribution is important and you mention you feel somewhat cramped when in the drops. This could be affecting your weight distribution and contributing to your uneasiness.

However, like Danl1 said, it's probably lack of confidence due to no practice.
 

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no....

Mel Erickson said:
Steering at speed is almost all body lean and very little actual steering input.
Anyone who has ridden a motorcycle or bike though mountain hairpin turns knows that is not true. It takes constant countersteering or the bike will want to go straight. Ride a Colango through a hairpin sometime, you'll figure that out real quickly. Sure the bars are turned a very small distance, but pressure must be constant (on the right side to turn right). Quit pushing on the bars and you'll be over the centerline in a hurry. This is a common cause of motorcyle wrecks. The rider doesn't push hard enough on the bars in a right hand turn, the motorcycle heads toward the centerline and in a last ditch panic, the rider quits pushing and goes into the oncoming lane.

I've posted many times that stem length has little effect on the steering arm length. A change from an 80mm to 120mm is about 15%.

Changing from a 40mm to 44mm bar is about 10%. Not a big deal either.
 

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Descending is all in the head. The more anxious you are, the slower you go, you just gave a very nice proof with your post :thumbsup:
 

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There's no magic in descending; it takes skill, practice, and a proper mindset. By no magic, I mean changing your stem length will not turn you into Sean Yates. And most geometries are so within a narrow range of known specs that work that it's almost impossible to buy a frame that doesn't descend well.

You need to get over your fear.
 

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naranjito
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I agree with the idea that it's probably just lack of practice. What makes a big difference for me though, and nobody has mentioned, are tyres. When descending on the limit, the differences between good and bad tyres are noticeable. Pressure is also very important, so pay attention to that too. Some bikes do descend better than others - I've always been a pretty fast descender, but when I changed from an alu orbea to a pinarello paris a few years ago, I really noticed the difference. I can take the pina through corners faster and with more confidence than I could with the orbea.

foz
 

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Hmmm... I always feel like the back end is a little "bouncy" on descents and I have a BB drop of 65, so... I was wondering whether it was geometry or if I should push the seat back a notch.
 

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n00bsauce
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We're essentially talking about the same thing. There are two components to steering. The actual twisting of the handlebars and the transfer of weight. At slow speeds we rely on the twisting of the handlebars for steering. At high speeds it's more weight transfer. Pressure on the bars is essentially weight transfer.
 

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n00bsauce
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Well, there is one significant frame/fork issue that's not directly related to descending skill, practice and mindset and that's speed wobble. Mohair is not claiming this to be a problem but if you do have speed wobble it's cause is not you, it's the bike. It takes skill to deal with but it's not a lack of skill that causes it.
 

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nope...

Mel Erickson said:
We're essentially talking about the same thing. There are two components to steering. The actual twisting of the handlebars and the transfer of weight. At slow speeds we rely on the twisting of the handlebars for steering. At high speeds it's more weight transfer. Pressure on the bars is essentially weight transfer.

You might think so, but no. If don't push on the bars to countersteer, the bike won't lean so that it can be turned. Most people do this without thinking until they get into a situation where the bike is not leaning sufficiently to follow a tight turing radius, then they don't know what to do about it. You can lean your body all you want, but it won't make a bicycle turn and it certainly will not make a motorcycle turn.
 

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OUTLAW BIKER
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mohair_chair said:
I have never been one of those fearless descenders that flies down hills with reckless abandon, but I was no ninny, either. I loved speed and pushed my limits, but I never could let go completely, and always held back a little.

After I slid out and crashed while leaning into a tight turn at about 35 mph, I got a little gun shy and lost a little more of whatever edge I had, but I still had no problems going down hill fast and carving out turns. I was just a little slower.

Fast forward a few years. Now I ride a fraction of the miles I used to (for various reasons), and don't get up into the mountains very often. A few weeks ago, I descended a local climb that is normally a fun, fast and twisty descent. I started down and quickly realized that I had zero confidence in what I was doing. I was scared. I couldn't wait to get off the mountain, but it was a five mile descent, so it was going to take a while. I was very relieved when I hit the bottom.

Here's my question. I got a new bike a year or two ago, which fits me better than any bike I've ever owned. It has a 70mm stem, which is quite short. On the hoods, where I spend most of my time, the fit is perfect, but in the drops or on the tops it feels a little cramped. I'm sure this was part of why I lacked confidence on the bike (along with being rusty at descending). I know stem length affects steering speed, so is this true? Could the short stem have contributed to my lack of confidence? Would going to a longer stem help?

Very true, but keep in mind that as with all things... practice, practice, practice....
The quicker steering - less leverage makes it twitchy = scary
Annnnd...
You haven't done it in a while.

Once I started Motorcycling (15 years ago), everything on my bicycle seemed so much easier. No, I'm not telling you to go out and get a motorcycle but it did put things into perspective....
Best of luck.:thumbsup:
 
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